That would probably be the Allison 250 series turboshaft engine.
There are many different helicopter engines, most of them now jets
One of the biggest contributing factors to a helicopter accident or crash is inclement weather and wind. Because of the size of a helicopter it can experience more turbulence than a plane. The second most common factor in helicopter accidents is malfunctioning instruments in the cockpit.
most look like a small jet engine
The Marines use many helicopters. Their most common helicopter is probably the AH-1 W Super Cobra
A helicopter with a jet engine. The engine is adapted to give power to a transmission, rather than thrust.
the engine
if the engine fails a good pilot can 'auto rotate' using the dead rotor to lower the helicopter
No, a helicopter cannot go at the speed of Mach 1.5. It is because, this kind of propulsion can only be achieved through a jet engine. A helicopter's engine cannot achieve that.
The Robinson 22 helicopter has a four cylinder pistol engine. The single-engine light utility helicopter was designed in 1973 and has been in production since 1979. The cost of one of these helicopters is about $270,000.
You can't do that.
you turn off the engine
The Chinook helicopter is an American twin-engine helicopter. The helicopter is used by military forces. The Chinook helicopter is mainly used for troop transportation, artillery movement, and resupply on the battlefield.